Self-knowledge and scepticism

Donald Davidson has argued that most of our beliefs must be true and that global scepticism is therefore false. Davidson's arguments to this conclusion often seem to depend on externalist considerations. Davidson's position has been criticised, however, on the grounds that he does not defeat the sceptic, but rather already assumes the falsity of scepticism through his appeal to externalism. Indeed, it has been claimed that far from defeating the sceptic Davidson introduces an even more extreme version of scepticism according to which we cannot even know the contents of our own minds. This paper argues that these criticisms are mistaken and that Davidson does indeed have grounds to argue that scepticism is false. The externalism that figures in Davidson's antisceptical arguments is shown to be merely an element in Davidson's overall holism according to which the very possibility of having beliefs that could be true or false depends on most of those beliefs being true and their contents known.